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Comment by rustyconover | Hacker News Reader

I think you'd be surprised how efficient video codecs with regards to bandwidth used, nobody sends raw pixels at all. Also with HLS latency can be very short with the right settings.

A few tips for coding screencasting:

For coding screencasts you should make sure that chroma subsampling isn't enabled when you're doing the encode of the video otherwise it may look worse with highly contrasting areas.

Decrease the encoding frame rate if its primarily going to be just a screencast without a lot of motion on the screen. At the expense longer mpeg segments (and more latency) you may want to increase the group-of-picture size.

There shouldn't be a reason that the encoded screencast looks worse then how it appeared to you unless the encoder you are using is just mashing the quality down.

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> For coding screencasts you should make sure that chroma subsampling isn't enabled when you're doing the encode of the video otherwise it may look worse with highly contrasting areas.

What platforms support 4:4:4 video? Youtube, Twitch, Vimeo, ... all don't.

I'd just build my own HLS setup with Cloudfront and one of those encoders with MediaLive.

> I think you'd be surprised how efficient video codecs with regards to bandwidth used, nobody sends raw pixels at all. Also with HLS latency can be very short with the right settings.

We've all had enough experience with Zoom, Google Meet, Skype for Business, etc. in recent months to know that this is not something that works well out of the box. And that's before we get into issues like the fact that I'm using a 34" ultrawide monitor, and most streaming systems will have to downscale my desktop before encoding it, and the result won't look at all good for a viewer trying to watch on a 1080p laptop.

At the same time, moving video coming from a camera is a lot different than a stream of what is essentially a 95% a still image.

I was referring primarily to the screen sharing features of the aforementioned services. In general, they're barely adequate for slideshow presentations, but the transitions are still going to be rough. And even when everybody in the virtual conference has a solid internet connection, the user experience is still a lot worse than when a PDF of the slides is emailed out before the meeting starts.

I find it simply amazing that all these "collaboration" tools aspire to little more than emulating the use-cases of broadcast television or a large lecture hall, and there a so few tools that try to enhance the experience in ways that are only possible when every participant has their own screen and computer.

Their badness is unrelated to the abilities of e.g. x264 compressing a screencast, because it really is quite good at that (near-losless quality at about one Megabit/s).

These systems are not OBS. You can pan and zoom as required to match your stream resolution, and it doesn't need to be the same as your desktop resolution.

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